Cable grips are used extensively in many industries to pull cable segments through conduit, along and between overhead towers, or in structural applications. Such grips are important tools for installation of both electrical and mechanical cables in, for example, bridge structures, hoisting and conveyor cables. Contemporary designs of cable grips were advanced during the first half of the twentieth century by Edgar Kellems, as described in part in U.S. Pat. Nos. 1,670,543, 1,886,026, and 2,664,609, each of which is incorporated herein by reference.
Commonly, a grip has a bore at one end and an eye portion at a distal end. With a cable which is to be pulled or secured placed in the bore, the grip is tightened about the cable and the eye portion is attached to a hook, or another cable or another type of mechanical linkage, in order to place the grip under tension. Such grips are generally fashioned as woven wire tubes with meshes of wire much smaller in gauge than the size of the cable inserted within the bore. Commonly, such grips are available in a large variety of sizes for application to mechanical cable and electrical wire varying in radial dimension from relatively small sizes such as used in residential electrical applications to large dimensions on the order of about two inches (5.08 cm) or greater. Cable grips are useful for pulling, positioning, routing and providing for strain relief of cables.
When attaching a grip to a cable, the grip is contracted along a longitudinal axis in order to enlarge the radial dimension of the bore about the longitudinal axis and thereby permit entry of the cable into the grip bore. Once the cable is positioned in the bore, the diameter of the bore opening is reduced to tighten the grip about the cable. Grips of this type are designed for limited ranges of cable size to assure that the grip can be used to reliably pull or secure the cable.